Method and device for the coordinated control of mechanical, electrical and thermal power flows in a motor vehicle

ABSTRACT

A method for the coordinated control of mechanical, electrical and thermal power flows in a motor vehicle for bringing about optimum operating states of units in the motor vehicle, and a device for carrying out the method. An optimum operating state (x opt ) for the unit system is determined in a module which receives as input variables at least the setpoint values provided by a second module after the variables determined by a third module have been combined together with additional specified variables in the second module, and the actual operating state (x) from a fourth module after the measured variables (y) resulting from the determination of the state of the units of the unit system have been combined in the fourth module; and after the optimum operating state (x opt ) for the unit system is determined, the setpoint operating state (x setpoint ) is determined in a fifth module, based on the actual operating state (x) and the optimum operating state (x opt ), so that due to this fifth module, a smooth transition is effected between the instantaneous operating state (x) and the operating state (x opt ) to be achieved.

FIELD OF THE INVENTION

The present invention relates to a method for the coordinated control ofmechanical, electrical and thermal power flows in a motor vehicle, suchas, for example, the drive power to the wheels, the rear window heatingand the interior climate control, for optimizing the consumption,comfort, emissions and dynamic vehicle response, and therefore forbringing about optimum operating states of units in the motor vehicle,including the storage systems, converters, transformers and the unitsfor dissipating energy; the invention also relates to a device forcarrying out the method for continuous control.

BACKGROUND INFORMATION

A number of conventional methods and devices for carrying out thesemethods exist for controlling power flows in a motor vehicle. DE 197 03863 A1, for example, describes a method and a device by which a drivecontrol is carried out, thus mechanical power flows in the motor-vehicledrive are controlled (see also Hötzer, D.: Entwicklung einerSchaltstrategie für einen PKW mit automatischem Schaltgetriebe(translated as “Development of a Shifting Strategy for a PassengerVehicle with Automatic Transmission”), Expert Verlag, Renningen, 1999).Regardless of how these methods operate, their goal is always tominimize the fuel consumption and optimize the vehicle response, whichcan be achieved by coordinated control of the internal combustion engineand the vehicle drive.

Other systems control thermal power flows in a motor vehicle, inparticular systems for thermal management and climate control, and yetother system control electrical power flows in the onboard electricalsystem such as systems for electrical energy management and for loadmanagement, as described for example in the article by Schöttle, R. andSchramm, D., Zukünftige Energiebordnetze im Kraftfahrzeug (translated as“Future Onboard Energy Networks in Motor Vehicles”), Fahrzeug-undVerkehrstechnik (“Automotive and Traffic Engineering”) Yearbook,VDI-Verlag, Dusseldorf, 1997.

However, conventional methods and systems share the common feature thatthey are principally concerned with only one form of energy in themechanical, electrical, or thermal power flows in a motor vehicle, and,therefore, essentially do not take into account the physical linkageprovided in a motor vehicle between these forms of energy.

SUMMARY

The present invention provides a method and a device for the coordinatedcontrol of mechanical, electrical and thermal power flows in a motorvehicle for optimizing consumption, comfort, emissions and vehicleresponse such that, by physically linking the storage systems formechanical, electrical, thermal and chemical energy, the converters forconverting the energy between these forms of energy, the converters forconverting the energy within one of the particular forms of energy, andthe units for dissipating energy of all forms, all forms of energypresent in a motor vehicle are taken into account.

These advantages are achieved by a method in which an optimum operatingstate x_(opt) for a unit system is determined in a “determination ofoptimum operating state” module which receives as input variables atleast the setpoint values provided by a “generation of setpointvariables” module after the variables determined by a “detection ofdriver intent” module have been combined together with additionalspecified variables in the “generation of setpoint variables” module, aswell as actual operating state x from a “determination of actualoperating state” module after measured variables y resulting from thedetermination of the state of the units of the unit system have beencombined in the “determination of actual operating state” module; andafter optimum operating state x_(opt) for the unit system is determined,setpoint operating state x_(setpoint) is determined in a “determinationof setpoint operating state” module based on actual operating state xand optimum operating state x_(opt), so that a smooth transition iseffected between instantaneous operating state x and operating statex_(opt) to be achieved.

The unit system is actuated by a vector of manipulated variables u, eachactuated unit having an input for control signals. Thus, ume stands fora converter of mechanical to electrical energy. Vector of manipulatedvariables u is determined by an “actuation of unit system” module insuch a way that operating state x_(setpoint) is established in the unitsystem. The actual control of the units of the unit system may beachieved in each particular case by a control unit—e.g., ME, EDC, orinverter control.

While measured variables y by which the state of the units of the unitsystem is detected are determined directly by sensors or, when measuredvariables y include derived variables, may be determined by unit controlunits, physical computational models are used for describing the units,and thus the unit system, when combining measured variables y anddetermining actual operating state x of the unit system in the“determination of actual operating state” module.

When the method according to one embodiment of the present invention iscarried out, variables ascertained by driver-assistance systems, forexample by a vehicle-speed controller or ACC, may be supplied by them asfurther specified variables to the “generation of setpoint variables”module. However, since the variables detected in the “detection ofdriver intent” module which result from the request for drive power tothe wheels, the request for electrical power which the onboardelectrical system must provide for operating electrical consumers suchas headlights, rear window heating and radio, and the request forthermal power for the interior climate control may also be supplied tothe “generation of setpoint variables” module as well, these variablesare combined, together with the variables determined by the driverassistance systems, in the “generation of setpoint variables” module.Setpoint variables for mechanical power P_(m,setpoint), electrical powerP_(e,setpoint), and thermal power P_(t,setpoint) are determined by this“generation of setpoint variables” module.

For determining an optimum operating state x_(opt), information aboutthe type of driver, the driving conditions and environmental variablesalso may be provided to the “determination of optimum operating state”module by a parameter vector a after detection by an additional module.

According to a further embodiment of the present invention, fordetermining optimum operating state x_(opt) in the “determination ofoptimum operating state” module, multiple possible operating statesx_(k) may be determined in real time during vehicle operation, so thatthe unit system supplies required mechanical power P_(m,setpoint),required electrical power P_(e,setpoint), and required thermal powerP_(t,setpoint). Operating states x_(k) are selected so that they satisfythe physical linkages, the limits of the storage systems and thecapacity of the units, a generalized consumption V being determined foreach operating state x_(k) according to the computing rule:

V = ɛ_(c) * v_(c)(a) * 𝕕Ec/𝕕t + ɛ_(m) * v_(m)(a) * 𝕕E_(m)/𝕕t + ɛ_(e) * v_(e)(a) * 𝕕E_(e)/𝕕t + ɛ_(t) * v_(t)(a) * 𝕕E_(t)/𝕕t

Likewise, for each operating state x_(k) the value of a power function Γis determined according to the computing rules:

G(x) = Y 1(a) * G1(x) + Y 2(a) * G2(x) + Y 3(a) * G3(x) + Y 4(a) * G4(x) + Y 5(a) * G5(x) + Y 6(a) * G6(x) + Y 7(a) * G7(x) + Y 8(a) * D8(x)and Γ(x) = V(x) − G(x) + Δ P(x),operating state x_(k) for which power function Γ assumes a minimum valuebeing determined as optimum operating state x_(opt).

In an alternative embodiment, for determining optimum operating statex_(opt) in the “determination of optimum operating state” module, asecond variant or another method step may be implemented, according towhich in offline optimization calculations, optimum operating statex_(opt) which minimizes power function Γ is determined for each vehiclespeed v and each required combination of required mechanical powerP_(m,setpoint), required electrical power P_(e,setpoint), and requiredthermal power P_(t,setpoint), the determination being made for variousvalues of parameter a. Optimum operating state x_(opt) is stored in amultidimensional characteristic map which is implemented in the“determination of optimum operating state” module and which containsinput variables v, P_(m,setpoint), P_(e,setpoint), P_(t,setpoint) and a,the output variable being optimum operating state x_(opt).

For carrying out the method for the coordinated control of mechanical,electrical and thermal power flows in a motor vehicle, the presentinvention also provides for a device in which an engine controlassociated with the internal combustion engine, a control, preferably inthe form of a pulse-controlled inverter, associated with the electricmachine, and a transmission control associated with the automatictransmission are connected via a CAN system to a vehicle control devicein which the method according to the present invention is implemented,the position of the accelerator pedal and thus the driver's request formechanical power P_(m,setpoint) for the drive being derivable using thevehicle control device. The vehicle control device specifies setpointengine torque M_(m,setpoint) for the engine control, setpoint torqueM_(e,setpoint) of the electric machine for the pulse-controlledinverter, and setpoint gear g_(setpoint) for the transmission control.In addition, by use of this device, electrical power requirementP_(e,setpoint) of the electrical consumers, as well as that of thepulse-controlled inverter connected to the onboard electrical system andthat of the battery, may be determined by the vehicle control device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts a system diagram of the units of the unit system of amotor vehicle, and the physical interconnection of these units,according to one embodiment of the present invention.

FIG. 2 depicts a schematic flow diagram of a control system by which themethod for coordinated control of the power flows in a motor vehicle isrealized according to one embodiment of the present invention.

FIG. 3 depicts a block diagram of the technical implementation of themethod for the drive train of a motor vehicle according to oneembodiment of the present invention.

FIG. 4 depicts a schematic flow diagram for determining the optimumoperating state in the “determination of optimum operating state” moduleshown in FIG. 2 according to one embodiment of the present invention.

DETAILED DESCRIPTION

The unit system according to FIG. 1 provides mechanical power P_(m),electrical power P_(e), and thermal power P_(t). The unit system mayinclude chemical, mechanical, electrical and thermal storage units whoseenergy contents may each increase, decrease, or remain constant. Theenergy content of the chemical storage may be represented by E_(c), thatof the mechanical storage by E_(m), that of the electrical storage byE_(e), and that of the thermal storage by E_(t). The rate of change ofthe energy content of the chemical storage is dE_(c)/dt, that of themechanical storage dE_(m)/dt, that of the electrical storage dE_(e)/dt,and that of the thermal storage dE_(t)/dt. The operating state of eachof the units may be characterized by a vector x_(i) whose elementsdescribe the state variables of the unit, for example rotational speed,torque, temperature and electrical current. For example:

-   -   The operating state of a converter of chemical to mechanical        energy, an internal combustion engine, for example, is described        by x_(cm);    -   The operating state of a converter of mechanical to electrical        energy, a generator, for example, is described by x_(me);    -   The operating state of a converter of electrical to mechanical        energy, an electric drive motor, for example, is described by        x_(em);    -   The operating state of a converter of electrical to thermal        energy, an electric heating device, for example, is described by        x_(et);    -   The operating state of a converter of chemical to electrical        energy, a fuel cell, for example, is described by x_(ce);    -   The operating state of a converter of mechanical to thermal        energy, a shaft bearing which must be cooled, for example, is        described by x_(mt); and    -   The operating state of a converter of chemical to thermal        energy, an auxiliary heater, for example, is described by        x_(ct).

The operating state of the transformers is described in an analogousmanner. For example:

-   -   The operating state of a chemical transformer, a methanol to        hydrogen reformer, for example, is described by x_(cc);    -   The operating state of a mechanical transformer, an automatic        transmission, for example, is described by x_(mm);    -   The operating state of an electrical transformer, a DC        converter, for example, is described by x_(ee); and    -   The operating state of a thermal transformer, a heat exchanger,        for example, is described by x_(tt).

Each of the units, including the storage systems, converters andtransformers, may appear multiple times in the unit system. Accordingly,additional operating states x_(i) are used for the description.

One unit may also convert multiple forms of energy. Thus, an internalcombustion engine converts chemical energy into mechanical and thermalenergy. The state of such a unit is likewise uniquely described by anoperating state, for example x_(cmt).

The unit system may provide multiple outputs for mechanical, electricaland/or thermal energy. Thus, for example, a unit system having a 14/42 Vdual-voltage onboard electrical system is provided both with an outputfor 14 V electrical consumers and an output for 42 V electricalconsumers. Multiple mechanical outputs are possible as well, for examplein utility vehicles having auxiliary drives.

The quantity of operating states x_(i) of the units and the energycontents of the storage systems may describe the overall operating statex of the unit system according to computing rule 1:

x = (E_(c), E_(m), E_(e), E_(t), x_(cm), x_(ce), x_(ct), x_(cc), x_(cd), x_(me), x_(mt), x_(mm), x_(md), x_(em), x_(et), x_(ee), x_(ed), x_(tt), x_(td)).

In the control system for coordinated control of the power flows andstates of the unit system according to FIG. 2, unit system 1 is actuatedby a vector of manipulated variables u. Each actuated unit has an inputfor control signals, for example ume for a converter of mechanical toelectrical energy. The actual control of the unit may be achieved ineach particular case by a control unit, for example ME, EDC, or invertercontrol. The state of the units of unit system 1 is determined by avector of measured variables y. These measured variables may beascertained directly by sensors (not further described), or also mayinclude derived variables that are determined by unit control units.Measured variables y are combined, and actual operating state x of unitsystem 1 is determined in a “determination of actual operating state”module 2. To this end, physical computational models may be used fordescribing the units and unit system 1, including for example observers.

The driver's intent is detected in a “detection of driver intent” module3. This module detects in particular the request for drive power to thewheels, the request for electrical power which the onboard electricalsystem must provide for operating electrical consumers such asheadlights, rear window heating and radio, and the request for thermalpower for the interior climate control. Driver assistance systems 4 mayalso generate specified variables. They are combined with the variablesdetermined by the “detection of driver intent” module 3 in a “generationof setpoint variables” module 5. This module determines setpointvariables for mechanical power P_(m,setpoint), electrical powerP_(e,setpoint), and thermal power P_(t,setpoint). Each of these setpointvariables may appear multiple times.

“Determination of optimum operating state” module 6 forms the core ofthe control system. This module determines an optimum operating statex_(opt) for unit system 1. It receives as input variables the setpointvalues from “generation of setpoint variables” module 5, and receivesactual operating state x from “determination of actual operating state”module 2. In addition, information about the type of driver, the drivingconditions, and environmental variables is used which is provided by amodule 7 via a parameter vector a.

A “determination of setpoint operating state” module 8 determinessetpoint operating state x_(setpoint) based on actual operating state xand optimum operating state x_(opt). This module 8 may help ensure asmooth transition between instantaneous operating state x and theoptimum operating state x_(opt) to be achieved. An “actuation of unitsystem” module 9 determines a vector of manipulated variables u in sucha way that operating state x_(setpoint) is established in unit system 1.

Assuming that the method according to the present invention optimizesconsumption, comfort, emissions and dynamic vehicle response, ageneralized consumption V may be determined according to computing rule2:

V = ɛ_(c) * v_(c)(a) * 𝕕Ec/𝕕t + ɛ_(m) * v_(m)(a) * 𝕕E_(m)/𝕕t + ɛ_(e) * v_(e)(a) * 𝕕E_(e)/𝕕t + ɛ_(t) * v_(t)(a) * 𝕕E_(t)/𝕕t

Factors ε are energy equivalence numbers which describe the varying rateof usability of the stored energies. Thus, the energy stored in thestorage for mechanical energy has a higher energy equivalence numberthan the chemical energy stored in the fuel tank. The values of theenergy equivalence numbers may be adapted on a long-term basis duringvehicle operation.

Factors ν(a) are weighting factors which weight the changes in theenergy content of the individual storage units. Their values aredetermined as a function of a parameter vector a. This parameter vectora describes, among other things, the type of driver (sporty,economical), the driving conditions (curve, city driving), andenvironmental variables (grade, roadway class, temperature).Environmental variables may also include information about the course ofthe roadway ahead and information which telematic systems are able toprovide, in particular curvature of the roadway ahead, grade of theroadway ahead, distance to the next intersection, etc.

Generalized quality gauges G_(i) for optimizing dynamic vehicleresponse, emissions and comfort may be defined as a function ofoperating state x of unit system 1. For example:

-   -   A quality gauge G1(x) describes the dynamic power reserve for        mechanical energy with respect to an operating state x. The        dynamic power reserve for mechanical energy indicates what        additional mechanical energy—beyond mechanical energy P_(m(x))        supplied for operating state x—unit system 1 is able to provide        for operating state x with high time dynamics. For a vehicle        drive with an electric motor and an internal combustion engine,        the dynamic power reserve for mechanical energy depends, for        example, on the maximum power of the internal combustion engine        for the internal combustion engine speed at operating state x,        on the maximum power of the electric motor at the electric motor        speed for operating state x, and the charge state of the        battery.    -   A quality gauge G2(x) describes the dynamic power reserve for        electrical energy in connection with an operating state x. The        dynamic power reserve for electrical energy indicates what        additional electrical energy—beyond electrical energy P_(e(x))        supplied for operating state x—the unit system is able to        provide for operating state x with high time dynamics.    -   A quality gauge G3(x) describes the dynamic power reserve for        thermal energy for an operating state x. The dynamic power        reserve for thermal energy indicates what additional thermal        energy—beyond thermal energy P_(t(x)) supplied for operating        state x—unit system 1 is able to provide for operating state x        with high time dynamics.    -   A quality gauge G4(x) describes the emission of air pollutants        (HC, CO, NO_(x)) for an operating state x. Large values for        G4(x) may be obtained for low emissions.    -   A quality gauge G5(x) describes the noise emissions in the        vehicle surroundings for an operating state x, large values for        G5(x) may be obtained for low noise emissions.    -   A quality gauge G6(x) describes the vibrational comfort for the        vehicle passengers for an operating state x. A large value for        G6(x) may correspond to a high comfort level.    -   A quality gauge G7(x) describes the sound emissions in the        vehicle interior for an operating state x. A large value for        G7(x) may correspond to low sound emissions.    -   A quality gauge G8(x) describes the wear on the units and        storage units for an operating state x. A low rate of wear,        i.e., a long operating life, may be described by large values        for G8(x).

An overall quality gauge G(x) may be determined according to computingrule 3:

G(x) = Y 1(a) * G1(x) + Y 2(a) * G2(x) + Y 3(a) * G3(x) + Y 4(a) * G4(x) + Y 5(a) * G5(x) + Y 6(a) * G6(x) + Y 7(a) * G7(x) + Y 8(a) * G8(x)

The values of weighting factors γ(a) are determined as a function ofparameter vector a.

For optimizing consumption, comfort, emissions and vehicle response, themethod according to one embodiment of the present invention minimizes apower function according to computing rule 4:Γ(x)=V(x)−G(x)+ΔP(x).

Power deviation ΔP(x) describes the deviation of the powers supplied byunit system 1 from the setpoint powers according to computing rule 5, asfollows:

Δ P(x) = ∏m(a) * (Pm, setpoint − Pm(x)) + ∏e(a) * (Pe, setpoint − Pe(x)) + ∏t(a) * (Pt, setpoint − Pt(x)).

Weighting factors πm(a), πe(a) and πt(a) are set as a function ofparameter vector a.

Alternatively, two different methods may be carried out for determiningoptimum operating state x_(opt) in “determination of optimum operatingstate” module 6 according to one embodiment of the present invention:

-   1. Multiple possible operating states x_(k) may be determined in    real time during vehicle operation, so that the unit system provides    required mechanical power P_(m,setpoint), required electrical power    P_(e,setpoint), and required thermal power P_(t,setpoint). Operating    states x_(k) may be selected so that they satisfy the physical    linkages, the limits of the storage systems, and the capacity of the    units. A generalized consumption V may be determined for each    operating state x_(k) according to computing rule 2. Likewise, the    value of a power function Γ may be determined for each operating    state x_(k) according to computing rules 3 and 4. The operating    state for which the power function assumes a minimum value is    specified as optimum operating state x_(opt).-   2. In offline optimization calculations, for each vehicle speed v    and for each required combination of required mechanical power    P_(m,setpoint), required electrical power P_(e,setpoint), and    required thermal power P_(t,setpoint), optimum operating state    x_(opt) is determined which minimizes power function Γ. The    determination may be made for various values of parameter a. Optimum    operating state x_(opt) may be stored in a multidimensional    characteristic map which contains input variables v, P_(m,setpoint),    P_(e,setpoint), P_(t,setpoint), and a. The output variable of the    multidimensional characteristic map may be optimum operating state    x_(opt). The multidimensional characteristic map is implemented in    “determination of optimum operating state” module 6.

The implementation of the method for coordinated control of mechanical,electrical and thermal power flows in a motor vehicle is described inone embodiment shown in FIG. 3 based on the drive train of the motorvehicle having an electric machine 12 situated on crankshaft 10 ofinternal combustion engine 11, thus a crankshaft start generator.Whereas internal combustion engine 11 is controlled by engine control13, electric machine 12 is controlled by a pulse-controlled inverter 14.Automatic transmission 15 is controlled by transmission control 16. Thiscontrol, in addition to engine control 13 and pulse-controlled inverter14, are connected via a CAN system 17 to a vehicle control device 18 inwhich the method according to the present invention is carried out.Vehicle control device 18 determines the position of accelerator pedal19 and from it, deduces the driver's request for mechanical powerP_(m,setpoint) for the drive. Vehicle control device 18 specifiessetpoint engine torque M_(m,setpoint) for engine control 13 andspecifies setpoint torque M_(e,setpoint) of electric machine 12 forpulse-controlled inverter 14. Setpoint gear g_(setpoint) is specifiedfor transmission control 16. Pulse-controlled inverter 14 is connectedto the onboard electrical system, to which the electrical consumers anda battery 20 are also connected. Vehicle control device 18 maydetermine, via electrical consumer devices, the need for electricalpower P_(e,setpoint) by the electrical consumers.

The determination of optimum operating state x_(opt) in “determinationof optimum operating state” module 6 according to FIG. 2 is describedbelow with reference to the schematic flow diagram according to oneembodiment of the present invention shown in FIG. 4.

Setpoint transmission output torque M_(ga,setpoint) is determined fromrequired mechanical power P_(m,setpoint) according to computing ruleM_(ga,setpoint)=P_(m,setpoint)/nga, where nga is the transmission outputspeed. Setpoint transmission input torque M_(ge,setpoint) is calculatedto be M_(ge,setpoint)=M_(ga,setpoint)/mueg, where mueg denotes thetorque amplification of automatic transmission 15 at the instantaneouslyengaged gear.

For the drive train shown in FIG. 3, the following relationshipaccording to computing rule 6M _(ge) =M _(m) +M _(e)is valid, where M_(m) describes the effective engine torque and M_(e)describes the torque of electric machine 12. The operating state of unitsystem 1 is characterized by computing rule 7x=(M _(m) , M _(e) , g, nga)where g describes the engaged transmission gear and nga describes thetransmission output speed. Engine speed nm and speed ne of electricmachine 12 are equal, and are specified by gear g and transmissionoutput speed nga.

Possible operating states x_(k) are determined by varying torque M_(e)of electric machine 12, within the limits of the characteristic curvefor the minimum and maximum torque, in discrete steps using anapplicable increment.

Electrical power P_(elm) of electric machine 12 results from torqueM_(e) and speed ne of electric machine 12, using a characteristic map.Positive torques (machine operating in drive mode) result in electricalpower consumption (P_(elm)<0). Negative torques (machine operating ingenerator mode) result in electrical power output (P_(elm)>0). Theelectrical power output of battery 20 is calculated from requiredelectrical power P_(e,setpoint) and the power consumed/output byelectric machine 12, according to computing rule 8:P _(batt) =P _(elm) −P _(e,setpoint)

Subsequently, only operating states x_(k) for which P_(batt) is in apredetermined interval are pursued further. This interval may be set asa function of charge state SOC of battery 20.

From P_(batt), dE_(e)/dt is determined using an efficiencycharacteristic map for battery 20. dE_(c)/dt is determined from thesetpoint engine torque obtained according to computing rule 9M_(m,setpoint)=M_(ge,setpoint)=M_(e)and a consumption characteristic map of internal combustion engine 11.Variables dE_(m)/dt and dE_(t)/dt are set to zero in the applicationexample. Using computing rules 2, 3, and 4, the operating statex _(k)=((M _(ge,setpoint) −M _(e,k)), (M _(e,k)), g, nga)is selected for which Γ assumes a minimum. Setpoint operating statex_(setpoint) is set equal to optimum operating state x_(opt). Themanipulated variables for the units, determined in “actuation of unitsystem” module 9 in FIG. 2, are M_(m,setpoint), M_(e,setpoint) andg_(setpoint).

In the described sequence, gear g_(setpoint) is not varied; rather, itis assumed that the gear is predetermined from an arithmetic block fortransmission control. However, in a further advantageous embodiment thesetpoint gear may be determined by the optimization method in“determination of optimum operating state” module 6 according to FIG. 2.To this end, the above-described computing steps are performed for theinstantaneous gear as well as for the next higher and next lower gear.The gear for which power function Γ assumes a minimum is determined asthe optimum gear.

Key to FIGS. 2 and 4:

-   -   soll=setpoint

1. A method for a coordinated control of mechanical, electrical andthermal power flows in a motor vehicle bringing about optimum operatingstates of at least one unit in the motor vehicle, the method comprising:determining, in a “detection of driver intent” module, at least onedriver intent variable; generating, in a generation of setpointvariables module, at least one setpoint value as a function of combiningthe at least one driver intent variable and an additional specifiedvariable; determining, in a determination of actual operating statemodule, an actual operating state as a function of at least one measuredvariable, the at least one measured variable determined from the stateof the at least one unit of the unit system; determining, in adetermination of optimum operating state module, an optimum operatingstate for a unit system as a function of the at least one setpoint valueand the actual operating state; and determining, in a determination ofsetpoint operating state module, a setpoint operating state for the unitsystem as a function of the actual operating state and the optimumoperating state, wherein the setpoint operating state is used togenerate a smooth transition between the actual operating state and theoptimum operating state; wherein the determining, in the determinationof optimum operating state module, the optimum operating state stepincludes determining a plurality of possible operating states in realtime during a vehicle operation so that the unit system supplies arequired mechanical power, a required electrical power, and a requiredthermal power, and wherein the possible operating states are selected inorder to satisfy physical linkages, limits of the storage systems andcapacities of the units, a generalized consumption determined for eachoperating state according to a computing rule:V = ɛ_(c) * v_(c)(a) * 𝕕E_(c)/𝕕t + ɛ_(m) * v_(m)(a) * 𝕕E_(m)/𝕕t + ɛ_(e) * v_(e)(a) * 𝕕E_(e)/𝕕t + ɛ_(t) * v_(t)(a) * 𝕕E_(t)/𝕕t.2. The method according to claim 1, wherein the unit system is actuatedby a vector of manipulated variables, an actuated unit having an inputfor a control signal.
 3. The method according to claim 2, wherein thevector of manipulated variables is determined by an actuation of unitsystem module in order to establish the setpoint operating state in theunit system.
 4. The method according to claim 3, wherein the at leastone unit of the unit system is controlled by a control unit.
 5. Themethod according to claim 4, wherein the measured variable is at leastone of ascertained directly by a sensor and, when the measured variableincludes a derived variable, determined by the unit control unit.
 6. Themethod according to claim 5, wherein a physical computational modeldescribes the at least one unit and the unit system when combining themeasured variable and determining the actual operating state of the unitsystem in the determination of actual operating state module.
 7. Themethod according to claim 6, wherein the additional specified variableis ascertained by a driver-assistance system, including at least one ofa vehicle-speed controller and an ACC, and is supplied by thedriver-assistance system to the generation of setpoint variables module.8. The method according to claim 6, wherein the additional specifiedvariable is detected in the detection of driver intent module as afunction of at least one of a request for drive power to the wheels, arequest for electrical power which the onboard electrical systemprovides for operating electrical consumers, and a request for thermalpower for an interior climate control.
 9. The method according to claim7, wherein a setpoint variable for mechanical power, a setpoint variablefor electrical power, and a setpoint variable for thermal power aredetermined by the generation of setpoint variables module.
 10. Themethod according to claim 9, wherein a data item, detected by anadditional module, including information about at least one of a type ofdriver, a driving condition, and an environment variable is provided toa determination of optimum operating state module by a parameter vector.11. A method for a coordinated control of mechanical, electrical andthermal power flows in a motor vehicle bringing about optimum operatingstates of at least one unit in the motor vehicle, the method comprising:determining, in a detection of driver intent module, at least one driverintent variable; generating, in a generation of setpoint variablesmodule, at least one setpoint value as a function of combining the atleast one driver intent variable and an additional specified variable;determining, in a determination of actual operating state module, anactual operating state as a function of at least one measured variable,the at least one measured variable determined from the state of the atleast one unit of the unit system; determining, in a determination ofoptimum operating state module, an optimum operating state for a unitsystem as a function of the at least one setpoint value and the actualoperating state; and determining, in a determination of setpointoperating state module, a setpoint operating state for the unit systemas a function of the actual operating state and the optimum operatingstate, wherein the setpoint operating state is used to generate a smoothtransition between the actual operating state and the optimum operatingstate; wherein the determining, in the determination of optimumoperating state module, the optimum operating state step includesdetermining a plurality of possible operating states in real time duringa vehicle operation so that the unit system supplies a requiredmechanical power, a required electrical power, and a required thermalpower, and wherein for each possible operating state the value of apower function is determined according to computing rules:G(x) = γ1(a) * G1(x) + γ2(a) * G2(x) + γ3(a) * G3(x) + γ4(a) * G4(x) + γ5(a) * G5(x) + γ6(a) * G6(x) + γ7(a) * G7(x) + γ8(a) * G8(x)and Γ(x) = V(x) − G(x) + Δ P(x), the operating state for which the powerfunction assumes a minimum value specified as the optimum operatingstate.
 12. The method according to claim 11, wherein in offlineoptimization calculations the optimum operating state which minimizesthe power function is determined for each vehicle speed and eachrequired combination of the required mechanical power, the requiredelectrical power, and the required thermal power, the determinationbeing made for various values of a parameter vector.
 13. The methodaccording to claim 12, wherein the optimum operating state is stored ina multidimensional characteristic map which is implemented in thedetermination of optimum operating state module, the multidimensionalcharacteristic map containing input variables including the vehiclespeed, the required mechanical power, the required electrical power, therequired thermal power, and the parameter vector, and an output variablebeing the optimum operating state.